Tooth brush and process of making



Sept. 5, 1.939. w. E. HILL er AL AME TOOTH BRUSH AND PROCESS OF MAKING THE S Original Filed April '7, 1935 5ms/f band/e .Bf/1s #es B/vls/es /m/o/egnafeo wif/2 non-729Mo germ/c/da/ csok/77m f 1 l. Maf/e3 off/asd 3f/weg awed mmap/lenta@ /'/7 vdc'uum oven Ey wia/puf Reima sept". 5, 1939 UNITED ,STA'AFILSl PATENT prima?,

TOOTH BRUSH AND PROCESS OF ltIAKlNGr THE SAME Warren E. Hill, Northampton,-Mass., and Clifford `I... McArthur, Birmingham, Mich., as'signors to Pro-Phy-Lac-Tic Brush Company, Northampton, Mass., a. corporation of Delaware Original No. 2,099,688, dated November 23, 1937,

Serial No. 664,894, April 7, 1933. Application for reissue April 14, 1938, Serial No. 202,046

s claims. (ci. soo- 21)` Our invention relates to brushes, such for example, as tooth brushes and to a process of -mal:- ing such brushes.

One of the objects of our invention is to pro-A vide an antiseptic or self-sterilizing toothbrush.

Another object of the invention is to provide av tooth brush of the foregoing character in which the bristles thereof are substantially impervious to moisture.

A further object oi the invention is to pro'vide an improved process bywhich tooth brushes having the aforesaid characteristics may be produced. Other objects and advantages of the invention will appear from the following description and appended claims. 1

`The invention will be more clearly understood from the following description in conjunction with the accompanying drawing, in which;

Fig. lis a longitudinal elevational view o, a

. brush embodying the invention;

Fig. 2 is a diagrammatic view illustrating the steps of the method of treating the'bristles after assemblywith 'the brush handle; and` Fig. 3 is a diagrammatic view illustrating the steps in the method of treating the bristles before they have been assembled with the brush handle.

Before explaining in detail the present invention it is to be understood that the phraseology or terminologyr employed herein is for the purpose of description and not of limitation, and it is not intended to limit the invention claimed herein beyond the requirements of the prior art.

It is well known that bacteria, fungi, mold and other like organisms ordinarily become associated with the bristles and the bristle end of tooth brushes either through useY when brushing the teeth or from the atmosphere and various articles with which the tooth brush may be associated or come in contact. Chieiiy for reasons of both health and appearance, it has long been desired to produce a tooth brush which Will-inhibit or kill these organisms even after prolonged periods of use. It is, therefore, a purpose of our invention to provide such a brush. In accordance with our inventionthe bristles.

before being assembled with the brush, may be rendered antiseptic, or, if desired, the brush head with the bristles assembled therein may be immersed in an antiseptic solution to sterilize the bristles. Inthe latter case, the bristles in the completed brush 'may be immersed in the antiseptic'solution, with little or no contact of said solution with the brushihead.

We have found that our process can be carried -associated with the bristles.

`vdiil'erent conditions. sometimes'the brush bristles become slightly dis- 4out successfully by the use 'of any one of the following antiseptic solutions, all of which have been given very satisfactory results. 'In its broader aspects, the process of our invention con* templates immersing the head of the brush with -5 the assembled bristles (or the bristles alone before their assembly with the brush) in a solution containing ingredients having antiseptic properties, for a period of time sumcient to allow an adequate amount of the. antiseptic agent to' 10 penetrate into or become absorbed by the bristles,

'the length of time of the immersion depending upon the rate at which the solution penetrates the bristles, and also upon the strength oi the circum- 15 antiseptic solution. Under certain stances, it maybe desired to impregnate the bristles at pressures other than atmospheric. The impregnation may then be carried on at either reduced or increased pressure, or any combination of pressures whereby adequate impreg- 20 nation, as herein described, is accomplished.- The brush is then removed from the solution and dried, preferably, 'in a vacuum oven, at a temperature of approximately F. for a sufficient period of time to remove the solvent of 25 `the solution, leaving the antiseptic agent closely The temperature within the oven should be kept at a degreewhich will not injure either the brush or the bristles. 'Ihe length of time required ior the drying oper- 30 Vation depends upon the temperature maintained solvents; such solutions will contain approxi- 45A mately 0.8 gram of antiseptic per liter oi water, or approximately 3 to 5 grams of antiseptic per liter in the case oi the other solvents mentioned. The proportions, however, may be varied to meet It has been found that 50 colored during treatment. To counteract this action and produce a pure white bristle, it may b e desirable to add `to the solution a small amount of any desirable coloring agent. One II such suitable agent is methylene blue. The coloringI agent used mustl of course. be one which will mix with the antiseptic solution and which is not objectionable for use on the tooth brush. l

If it is desirable to'produee an antiseptic tooth brush in which the bristles are impervious to moisture, then any ysuitable non-water-soluble are miscible.

material, such. for example, as vcertain waxes, waterproof cellulose-ester-base compositions,` or the like, may be added to the solution. Waxes, such as parafiine, ceresin. carnauba, etc., are

suitable for this purpose;v waterproof composi-' tionshaving as a 4basca cellulose ester or other suitable compound or derivative of cellulose may' be used. The waterproofing material may be dissolved in a solvent, and added to the solution of antiseptic agent. The two solvents are preferably miscible, so that a single-phase liquid will result after the two solutions are mixed.

Or.. if desired, the two solvents may be mixed first; or a suitable single solvent maybe used, and the antiseptic agent-and the waterproofing material may each be added thereto. For such purposes, -dioxane and toluol, for example, result in a good single-phase liquid. as the former dissolves the phenyl mercuric nitrate and the latter` the water-proofing agent, and the two solvents The waterproofing agent cooperates with Vthe antiseptic to retard diffusion of-the 'antiseptic dried upon the bristles when wetted for usage. v

`Other solvents than those mentioned may be used in preparing the phenyl mercuric nitrate solution. The solvent used should be chosen with reference to whether or not a waterproofing material is to be used, and -to various obvious factors such as solubility, eifect on color `and quality of the bristles, etc. Ethyl alcohol, acetone, benzol, ethyl acetate and certain other acetates, etc. may be usedalone or in admixture with each other or with the various solventsv hereinbefore set forth. As one example of this, we have used successfully a solution of, phenyl mercuric vnitrate in dioxane wherein a suitable part oi' the dioxane has been replaced by acetone while the amount of salt dissolved remains substantially'the same as though the solvent .were entirely dioxane.

Antiseptfic or germicidal solutions containing other ingredients may, of course, `be used.

Oxyquinoline sulfate', another e'ective germi-l cide, may be used in place of the phenyl mercuric salts. The process is the same, except that the sulfate, being much more soluble in water than .phenyl mercuricsalts. is not'ordinarily applied to the bristles in a saturated solution, but rather in a concentration of aboutA l part of sulfate to between 100 and 1000 parts of solvent. The concentration used should be sumcient to iinpart the desired germicidal activity.

It may be desirable to use para-chlorothymol as the antiseptic agent. This agent is not water soluble and the solution mustbe prepared with lanother solvent, such for example. as ethyl.

alcohol.

- It will be understood that when 'we refer to a solution we include, ofcourse, any dispersions,

emulsions-,Suspensions etc., of the germicide and/or the waterproofing agent in any. suitable fluid whereby the germicide and/or waterproofing agent may be brought into intimate association with the'bristles. Moreover. it Awill be understood that lthe antiseptic used is nontoxic and' it does not impart objectionable properties of color, taste or odor to the articles rendered antiseptic. I

From the foregoing it will ybe seen that we have provided a new article ofmanufacture and a process for producing it in which the process ,consista broadly, in immersing either the loose bristles before assembly with the brush, or the brush with the bristles assembled therein, in a solution 'containing a suitable antiseptic br gennicide which renders the bristles antiseptic `or self-sterilizing for a long period of time, ap-

proximating the useful life of the brush. The

immersion may take place at any convenient time during the manufacturing process. The process contemplates further the use in such solution of a suitable non-water-soluble material which renders the bristles impervious to moisture.

The drying of the sterilized bristles, or the brush with the assembled bristles, may be performed in a vacuum oven at any suitable noninjurious temperature, and, if desired, at a reduced pressure; or they may be subjected to air drying.

Wev claim:

l. The hereindescribed process of making an lantiseptic brush having .bristles which are impervious to moisture, which comprises immersing the brush head and bristles in a solution containing phenyl mercuric nitrate,` paraiiin wax vanrl toluol.

' 2. A process of making an antiseptic tooth brush having bristles which are impervious to `moisture which comprises treating the bristles with a solution containing an antiseptic, a

v waterproong agent and a solvent consisting of dioxane and toluol,

3'. A vprocess of making a self-sterilizing brush which comprises impregnating, the'bristles with a solution containing a waterproofing agent' and an antiseptic. 4. A brush having the bristles' thereof impregnated with an` antiseptic and a waterprooiing' with a waterproofing means and permeated with an antiseptic, said waterproofing means retard# ing diffusion oi the antiseptic when the bristles 'are wetted in usage.

WARREN E. HILL. g CLIFFORD L. MGARTH'UR. 

